A system of sequential extraction and cleaning coupled with high performance liquid chro-matography (HPLC) by multi-wavelength detection applied to the analysis of 46 synthetic pigments and dyes in food was established. The system of sequential extraction was composed of three grades. In the first grade of extraction, the Sudan dyes were extracted with n-hexane and cleaned effectively by gel permeation chromatography. The recoveries of 8 Sudan dyes were not less than 80%. In the second grade of extraction, most of water-soluble synthetic pigments were extracted with water assisted by acetonitrile. And the recoveries were not less than 60%. In the third grade of extraction, a few of compounds were extracted using methanol and ammonia water whose concentration was 1.0%. And the recoveries were not less than 55%. It was unnecessary to clean up the extract after the second and third grade of extraction. The detection results of samples from markets showed that the system of sequential extraction and cleaning was suitable for the food stuffs contained protein and fat.%建立了46种禁限用合成色素的分级提取净化体系,采用反相液相色谱多波长检测对该体系的效果进行了评价.提取净化体系的第一级采用正己烷振荡提取、凝胶渗透色谱净化,实现了对苏丹类染料的有效提取分离,回收率均大于80％；第二级采用水振荡提取,乙腈辅助提取的手段,实现了对大多数水溶性合成色素及工业染料的提取分离,回收率均大于60％；第三级采用甲醇-氨水振荡提取,可实现对少数极性较强染料的提取分离,回收率均大于55％.经过第二、三级提取后的样品,无需再净化,即可直接进行高效液相色谱分析,提高了分析效率.采用此体系对样品进行合成色素的测定分析,结果表明,本方法对含蛋白质、脂肪类食品基质具有较强的适用性.
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